Methods and apparatuses for requesting system information

Abstract

A method for requesting system information, includes: sending a first random access request, wherein the first random access request carries at least one pilot code for identifying system information to be requested; monitoring a response message corresponding to the first random access request within a preset time period, wherein the response message carries information for responding to the at least one pilot code; and when the response message is detected, based on a pilot code identifier included in the response message, monitoring and receiving system information corresponding to the pilot code identifier within a transmission window of the system information corresponding to the pilot code identifier.

The invention claimed is: 
     
       1. A method of requesting system information, comprising:
 sending a first random access request, wherein the first random access request carries at least one preamble for identifying system information to be requested; 
 monitoring a response message corresponding to the first random access request within a preset time period, wherein the response message carries information for responding to the at least one preamble; and 
 when the response message is detected, based on a preamble identifier included in the response message, monitoring and receiving system information corresponding to the preamble identifier within a transmission window of the system information corresponding to the preamble identifier, 
 wherein the response message has a format that only includes one or more sub-packet headers and does not include a packet body, and the preamble identifier is carried by a sub-packet header of the response message. 
 
     
     
       2. The method according to  claim 1 , further comprising:
 determining system information that is unsuccessfully requested, based on the preamble identifier included in the response message and the at least one preamble carried in the first random access request; and 
 sending a second random access request, wherein the second random access request carries a preamble of the system information that is unsuccessfully requested. 
 
     
     
       3. The method according to  claim 2 , further comprising:
 counting a number of requests for each piece of the system information to be requested; and 
 when the number of requests for a piece of the system information to be requested is greater than a preset threshold, indicating to a Radio Resource Control layer that the number of requests for the piece of the system information has reached a maximum threshold. 
 
     
     
       4. The method according to  claim 1 , further comprising:
 when no response message is detected, determining that none of the system information to be requested is successfully requested. 
 
     
     
       5. A method of sending system information, comprising:
 receiving a random access request sent by user equipment, the random access request carrying at least one preamble for identifying system information to be requested; 
 generating a response message with a preset format based on the random access request, wherein the response message has the preset format that only includes one or more sub-packet headers and does not include a packet body, and a preamble identifier is carried by a sub-packet header of the response message; and 
 sending the response message. 
 
     
     
       6. The method according to  claim 5 , wherein generating the response message with the preset format based on the random access request comprises:
 analyzing the at least one preamble for identifying the system information to be requested; and 
 obtaining the response message with the preset format by adding a pilot coda preamble identifier of a preamble of system information determined for response, to the sub-packet header of the response message. 
 
     
     
       7. The method according to  claim 5 , further comprising:
 sending the system information for response within a transmission window of the system information to be requested. 
 
     
     
       8. User equipment comprising:
 a processor; and 
 a memory to store instructions executable by the processor; 
 wherein the processor is configured to:
 send a first random access request, wherein the first random access request carries at least one preamble for identifying system information to be requested; 
 monitor a response message corresponding to the first random access request within a preset time period, wherein the response message carries information for responding to the at least one preamble; and 
 when the response message is detected, based on a preamble identifier included in the response message, monitor and receive system information corresponding to the preamble identifier within a transmission window of the system information corresponding to the preamble identifier, 
 wherein the response message has a format that only includes one or more sub-packet headers and does not include a packet body, and the preamble identifier is carried by a sub-packet header of the response message. 
 
 
     
     
       9. The user equipment according to  claim 8 , wherein the processor is further configured to:
 determine system information that is unsuccessfully requested, based on the preamble identifier included in the response message and the at least one preamble carried in the first random access request; and 
 send a second random access request, wherein the second random access request carries a preamble of the system information that is unsuccessfully requested. 
 
     
     
       10. The user equipment according to  claim 8 , wherein the processor is further configured to:
 count a number of requests for each piece of the system information to be requested; and 
 when the number of requests for a piece of the system information to be requested is greater than a preset threshold, indicate to a Radio Resource Control layer that the number of requests for the piece of the system information has reached a maximum threshold. 
 
     
     
       11. The user equipment according to  claim 8 , wherein the processor is further configured to:
 determine that none of the system information to be requested is successfully requested when no response message is detected. 
 
     
     
       12. A base station comprising:
 a processor; and 
 a memory to store instructions executable by the processor; 
 wherein the processor is configured to:
 receive a random access request sent by user equipment, the random access request carrying at least one preamble for identifying system information to be requested; 
 generate a response message with a preset format based on the random access request, wherein the response message has the preset format that only includes one or more sub-packet headers and does not include a packet body, and a preamble identifier is carried by a sub-packet header of the response message; and 
 send the response message. 
 
 
     
     
       13. The base station according to  claim 12 , wherein the processor is further configured to:
 analyze the at least one preamble for identifying the system information to be requested; and 
 obtain the response message with the preset format by adding a preamble identifier of a preamble of system information determined for response, to the sub-packet header of the response message. 
 
     
     
       14. The base station according to  claim 12 , wherein the processor is further configured to:
 send system information for response within a transmission window of the system information to be requested.